2.11BSD#431 - /usr/man/cat3/getservbyport.0

GETSERVENT(3N)	    UNIX Programmer's Manual	   GETSERVENT(3N)


NAME
     getservent, getservbyport, getservbyname, setservent,
     endservent - get service entry

SYNOPSIS
     #include <netdb.h>

     struct servent *getservent()

     struct servent *getservbyname(name, proto)
     char *name, *proto;

     struct servent *getservbyport(port, proto)
     int port; char *proto;

     setservent(stayopen)
     int stayopen

     endservent()

DESCRIPTION
     Getservent, getservbyname, and getservbyport each return a
     pointer to an object with the following structure containing
     the broken-out fields of a line in the network services data
     base, /etc/services.

	  struct    servent {
	       char *s_name;  /* official name of service */
	       char **s_aliases;   /* alias list */
	       int  s_port;	   /* port service resides at */
	       char *s_proto; /* protocol to use */
	  };

     The members of this structure are:

     s_name	The official name of the service.

     s_aliases	A zero terminated list of alternate names for the
		service.

     s_port	The port number at  which  the	service  resides.
		Port numbers are returned in network byte order.

     s_proto	The name of the protocol to use  when  contacting
		the service.

     Getservent reads the next line of the file, opening the file
     if necessary.

     Setservent opens and rewinds the file.  If the stayopen flag
     is non-zero, the net data base will not be closed after each
     call to getservbyname or .IR getservbyport .


Printed 11/26/99	  May 19, 1986				1


GETSERVENT(3N)	    UNIX Programmer's Manual	   GETSERVENT(3N)


     Endservent closes the file.

     Getservbyname and getservbyport sequentially search from the
     beginning of the file until a matching protocol name or port
     number is found, or until EOF is encountered.  If a protocol
     name  is  also supplied (non-NULL), searches must also match
     the protocol.

FILES
     /etc/services

SEE ALSO
     getprotoent(3N), services(5)

DIAGNOSTICS
     Null pointer (0) returned on EOF or error.

BUGS
     All information is contained in a static area so it must  be
     copied  if it is to be saved.  Expecting port numbers to fit
     in a 32 bit quantity is probably naive.


Printed 11/26/99	  May 19, 1986				2